Alerts sent to example@email.com, instead of provisioned mail address, leaking my system

### What happened? My setup is grafana/grafana-oss:12.3.2-ubuntu based docker container. I provisioned it via /etc/grafana/provisioning/alerting/contact-points.yml: ``` apiVersion: 1 deleteContactPoints: - orgId: 1 name: grafana-default-email contactPoints: - orgId: 1 name: Notification_Contact_Point receivers: - uid: des0c5977h6v4a type: email settings: addresses: $GRAFANA_NOTIFICATION_EMAIL_ADDRESSES singleEmail: false disableResolveMessage: false ``` and configured GRAFANA_NOTIFICATION_EMAIL_ADDRESSES via environment variable in docker compose. There seems to be a short time after deployment where Grafana is not yet completely provisioned with this config and instead uses an alternative default mail address "example@email.com" for alerting, which leaks my systems. See also https://github.com/grafana/helm-charts/issues/1819. ### What did you expect to happen? I expect the configuration to be used at all time, i.e. immediately after startup of Grafana. Until the configuration is from the provisioning files is applied, alerting should be effectively disabled at all. Most important: no alternative E-Mail public address should be used for alerting, as it would leak my system (security problem!). ### Did this work before? don't know if it ever worked before. ### How do we reproduce it? 1. setup and create docker container like described in the description, e.g. with docker compose. 2. in Grafana UI, open Alerting > Contact points. Check if the E-Mail address is used like provisioned. 3. in menu Alerting -> Settings, check the alert manager "Grafana built-in". Open it's configuration (Button "View configuration"). Open "Versions". After waiting for a view minutes, I can see two versions like in the screenshot: <img width="2438" height="505" alt="Image" src="https://github.com/user-attachments/assets/1affd1f1-c076-4137-a638-79450d74379d" /> Comparing the two versions shows the problem: the initial versio…